Wood-chipping machine



sept 18, 1921s.A 1,684,411 J. RAE

woon CHIPPING MACHINE Filed May 15, 1926 John Rae Afafngy Alva/vra@ fifi Patented Sept6 lf3, i923.

. Lflflll WOOD-CHPPENG MACHINE.

Application filed May 15,

My present invention relates to improvements in wood chippingmachine of the type commonly used for the purpose of cutting wood into chips preparatory to making pulp therefrom and appertains more particularly to a chute feeder therefor whereby the blocks of wood to be chipped are fed by gravity to a rotary knife-carrying disk.

It is common practice in wood chipping machines of this general type to provide a horizontal stationary knife associated withy the spout to coact with the rotary cutting` elements` the same being adjustable to compensate for wear incidental to the action of the blocks of wood during' the operation of the machine. ln use, such a machine is constantly requiring adjusting and replacements due to the excessive wear on the stationary knife at one point for when such knife is arranged horizontally the block is thrown violently against it everytime a blade on the rotary cutter strikes the block and this impact against the stationary knife is focused pretty much on one point. Consequently a certain part of the stationary knife is soon worn down by this unnecessarily severe treatmentand the blade rendered useless. Y

A further disadvantage of this type of chipper is that totally inadequate and oftentimes no provision at all is made to care for wear on the inner end of the feed spout as it approaches the knife and where such wear is occasioned; it frequently happens that the whole spout is discarded when the thrashing' of the blocks on a limited area of the mouth of the spout has so worn it that it has to be consigned to the scrap heap.

The objects of this invention are-to provide an improved spout wherein the associated iii-:ed knife is angularly disposed `and readily adjustable; adequate provision is made for replacing' worn sections of the spout and in which the spout as a unit is of generally improved construction comprising few and relatively simple parts, any of which are movable beingreadily accessible.

To the accomplishment of these and related objects, the'invention resides in the construction, combination and arrangement of the several co-operatine` elements as shall be hereinafter more fully described, illustrated in the accompanying;` drawings and pointed out the claims hereunto appended.

The invention can be best described and will be most readily understood when refer- 1926., Serial No. 109,404.

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Figs. 3, l and 5 are a front elevation, plan l and side elevationrespectively of the chute. ln this apparatus a suitable bed isprovided to support a rotatable disk in which a number of knives are arranged and an inclined chute disposed eccentric to the cutting ldisk that it so feeds to the same, the delivery mouth of such chute just clearing the knives of said rotary disk; This chute. eccentric to the axis of the rotary cutter, is inclined sufliciently to feed the wood blocks by gravity to the rotating knives and arranged at an angle to the vertical plane. rThe rotary knives therefore do not cutk directly across the grain. nor yet with it but at an anlele thereby eliminating to a large degree the breaking of the wood into splinters, splits. wood'dust and the like, the presence of which constituents in the wood chips when thesame go into the mash lowers the quality of the pulp so that the limiting, to as nearly total exclusion as possible, of the produc'-v tion of these elements is to be desired.l

Theusual harmful effects accompanying the thrashingof the wood blocks inthe spout are also lessened by forming the spout particularly at the feed end as aV V-shaped trough in which each block settlesto find a 'ISS conformable support or bed. The portions ..90

of these walls adjoining the delivery end are both adjustable and replaceable to allow of advancement to give the desired support to the block and removal when badlyl worn. In this way not only is the amount of wear on the'feed end of the spout, loccasioned by pounding or thrashing` materially curtailed but ample provision is made for caring for such as is inevitable while preserving the usefulness of the spout as a whole.

Supporting the fixed knife at an incline so that its exposed or cutting edge is angular to the horizontal plane has very marked advantages in imparting, in co-operating 'with the rotating knives, a shearing cut rather Vthan a direct chipping blow. The cuttinp; of chips free those undesirable elements that lower the grade of the pulp; lengthening' the life of the knife by distributing'the wear over a greater surface and incidentally saving time wasted in the unnecessarily frequent .adjusting'fand 'replacing ofthe lkn'ife; and the production of greater speed from the rotary cutter `by re-V ducing the resistance `of each .chipping blow are the principal features of the inclined knife but the reduction of vibration and the obtaining of higher eflic'iency in general are likewise attributesV of this :improved design.

Referring now particularly to the drawings wherein llike characters indicate like parts throughout the several views, the invention .is shown Aas vcomprising a bed or foundation 4support .6 on which a rotatable shaft 7 and a -feed chute 8 are mounted.

pit. Asuitableguard lliienclosesthefupper Vhalfoffthe diskcutter 10.y 1

The -chute '8 .is disposed eccentrically to the shaft 7 and so rinclined as to feed the woodblocks `to the chipper `disk 10, with `which :its Adelivery end communicates, `by gravity. The sameecomprises a shoe 15 hav- Y ing Ja flange 16, by which fit is frmlyan- -chored ltothe bed @extending around both --sides and the back, but .terminating flush with the mouth 17 ofthe spout confronting the rotar-yvchipper. "Theichuteinclines upwardly as-an arm from the delivery -mouth fand angularly .from the .vertical plane of the .longitudinal median of the shoe. 'This part Vof the chute Ais formed Aas 4a trough 18 substantially. Veshaped and is lcut away at the .mouth 1-7 to receive the square plates 19,k

removably fastened with-countersunk .screws 2O, that 1lie smooth with the face of the `trough andterminate flush -Withvthe mouth. The slots 21 in said plates adapted to vre- -ceive the retaining screws may be elongated .to render thesame adjustable.` A .removable top yis provided, for .the trough 18, ex- .tending `from the mouth to the tail of the chute land *carries a handle part 23. Locking'members 42li .serve to .retain the same in place; the top of the chute being thus fre- Jnovable, easy access `is provided to the replaceable plates 119.

The shoe 15 nearits base has aicut from frontftobackfand extending the widthfof the trough to accommodate a fixed, knife 25 that is inclined, one -side being raised considerably'a'bove the other, for a purpose hereinbefore described, but that .longitudinally lies horizontal. 'This knife '25 which `underlies the .trough 18 ris movable longitudinally to Y .compensate `for wear and also to permit a close vadjustment `of it with ,relation Ito the co-operating knives on the rotary disk 10, it being advantageous, to secure the best shearing, to .have no ,gap Vat .all between the 'fixed and moving knives. Accordingly, a regulating stem 26, suitably connected to the rear end of the knife 25, isthreaded in `an upstanding extension 27 of the rear flange 16 and adapted on rotation to advance to retard the knife. Aset screw 28 located in the top of said extension 27 designed toengage the stem vacts as a clamp therefore. It will be obvious that the size and shape of the wood blocks being fed to the chipper `will `have an influence on `the relation of the osition of the cutting edge of the fixed kni e to the mouthi of the trough for not every block will settle into contact with Vthe apex of the V` sidesconsequently the cutting yedge of 'the fixed knife should be adjustable to allow of so positioning this edge that `the same will lie `in the pathiof a projection from the line on the lower side :of theblock being chip ed if maximum support for the said `bloc is to be provided. From the foregoing description taken in connection with the accompanying drawings, it `will `be manifest that a wood chip ing machine is provided which will fulfill all the necessary requirements of such'adevice, 'but as many changes could be maderin the above description and many apparently Widely different embodiments of my invention constructed within the scope of the a pended claims without departing from t e spirit `or scope thereof, it is intended that `said chute being eccentric to the `axis of said disk and projecting to just clear' the knives of the latter; and a, `fixed knife disposed angularly to the horzontalplane and adapted `to coact with the knives of said disk.

2. In a chipper as described, the combination -of `a rotary knife-carrying disk; an inclined feed chute with a dat inclined removable top and a replaceable bottom, said chute `being `adapted to convey vthe wood blocks `into contact vwith the knives of said disk, `comprising a shoe lhavinga retaining Vflange about both'sides and the back and a trough partthat in addition to beinginclined from the horizontal plane is angular to the `vertical plane from the longitudinal median of the shoe; and an adjustable stationary knife adaptedto be advanced into the path of a projection from the line of the under side of a block being fed to the chip er.

3. In a chipper as described,"t e combinaanV tion of a rotary knife-carrying disk; an into back and extending the greater part of elined feed chute With a flat inclined removthe Width thereof, the same being higher able top and areplaeeable bottom, said chute at one side than the other; an adjustable being adapted to convey the Wood blocks stationary knife adapted to project through 5 into Contact With the knives of said disk, said eut; and means for regulating the loneomprising a shoe having a retaining flange gitudinal position of the last mentioned I about both sides and the back and a trough knife. part that in addition to being inclined from In testimony whereof I hereunto afIiX my the horizontal plane is angular to the vertisignature.

10 eal plane from the longitudinal median of Y the shoe; a out through said shoe from front JOHN RAE. 

